Thinking of adding an in-bed gas tank that might be semi permanent.
Has anybody here done this to a modern F150?
Does anybody know if you can just gravity drain into the tank or if the tank is pressurized in any way while it is running?
If I get a 15-20 gallon or more sized tank, when the gauge is down to 1/4 or less just flip the switch, energizing a solinoid, opening a valve and let the whole thing gravity flow into the original tank.

10 mpg while towing the camper only gets me 200 miles or so down the road and heading out West of the Mississippi there might be places where I would get into trouble with the 26 gal original tank. I know I could put in a 36 gal tank but that is only 10 more gallons and it is over $600 for just parts/shipping.

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Not sure if gravity feeding from tank to tank is legal. I'm sure plenty of people do it though. Transfer flow tanks make some nice in bed tanks. They are pricey though. There are a few more companys out, just can't recall them at the moment.

An aux tank needs to be tied into the fuel and emissions systems otherwise you'll get an emissions code on the Check Engine light.
You could rig a stand-alone tank and use a 12v fuel transfer pump to fill the truck tank, but you'd have to pull over to the side of the road to do it.

In looking at this (even though it is for diesel) I think I can make it work as the gas actually would be siphioned out of the top of the in-bed tank with a shut off valve and elect solenoid to actually stop flow and also by design to stop flow if there was a line failure (break siphion suction). http://www.ehow.com/list_7605045_law...sel-tanks.html

An aux tank needs to be tied into the fuel and emissions systems otherwise you'll get an emissions code on the Check Engine light.
You could rig a stand-alone tank and use a 12v fuel transfer pump to fill the truck tank, but you'd have to pull over to the side of the road to do it.

I work in the oil patch... Thats How EVERY RIG manager and DRILLER does it.

One guy decided to hard wire his pump in and lock the nozzle. Someone came by, cut the lock with bolt cutters, and filled his own truck.

our cummins 5500 has a 150gal bulk tank in the bed and we have a switched feed to the pump and fill when needed. just remember, the tanks weigh ~250, + 50gals of gas is another ~400lbs. that's 650lbs of payload out the window! I just strap two offroad quick fill tanks in the bed just in case I come up short in my personal rig.

our cummins 5500 has a 150gal bulk tank in the bed and we have a switched feed to the pump and fill when needed. just remember, the tanks weigh ~250, + 50gals of gas is another ~400lbs. that's 650lbs of payload out the window! I just strap two offroad quick fill tanks in the bed just in case I come up short in my personal rig.

I may end up doing that also. I was only going to get a 15-20 maybe 24 gal max tank so it would be just like hauling 2-3 5 gallon cans too. Just was looking for something a little more automatic.

Smaller, takes little space.http://www.northerntool.com/shop/too...6745_200306745
Other places like northern or fleet farm in my area have anything from about this up to roughly 100 gal tanks. Have found some 40-60 gal tanks that also have a toolbox built into them. Spendy tho, I hate my 26 gal tank too, but I'd personally put a 36 under the truck. When I need a lot of fuel is only in the spring and fall. We have a 90 or 100 gal. (can't remember) rectangular tank, but it only sees diesel.